This invention relates to a dental prophylaxis angle.
Dental prophylaxis angles, known also as "Prophy Angles", are dental instruments used for rotatably holding dental tools such as brushes or prophy cups having receptacles which hold a dental prophy composition for application to tooth surfaces with rotary motion.
These prophy angles typically include a body having a head at an angle relative to the body, most commonly 90 degrees. A drive shaft extends through the body to engage a drive gear incorporated in the angle for rotatably driving a tool located on the head. The body is attached to a handpiece which connects the drive shaft to a remotely located motor.
Because of its use in the mouth, the prophy angle must be either sterilizable or disposable, and a single use disposable angle is preferred. Consequently, a low cost yet reliable prophy angle is needed.
Various disposable prophy angles are known such as those described in U.S. Pat. Nos. 5,156,547, 5,040,978, or 5,028,233, among other. However, in each case, the number of parts and degree of complexity in assembly result in increased costs.
It is also desirable to provide prophy angles which incorporate a bend in a neck portion of the housing to facilitate movements within the mouth. However, many of the existing prophy angles are not easily modified by incorporating such a bend due to conflicts with the bearing system or other drive components. For example, the prophy angle of U.S. Pat. No. 5,040,978 includes an enlarged shaft portion which cannot tolerate such a bend.
It is also desirable to assure access to all tooth surfaces, particularly interproximal surfaces. Most disposable prophy angles currently on the market have a short cup rigidly mounted to a rotatable cup holder. In order to reach all dental surfaces, the clinician must work the dental handpiece back and forth and at various angles while applying considerable pressure to conform the cup to the tooth surfaces. In addition to patient discomfort, such use may give rise to repetitive movement injuries such as carpal tunnel syndrome.
One known disposable prophylaxis angle currently on the market has a relatively long prophy cup. Although this design increases cup flexibility, the larger size of the cup and associated prophy angle head makes it more difficult to treat all tooth surfaces and increases discomfort as the dentist maneuvers the large cup and angle within the mouth.